For what it's worth, 'Bogong volcano' is being shown about 25km SSW of the actual Mount Bogong (the highest in the state of Victoria at 1986m, but not a 'real mountain' by most people's standards). Mt. Bogong is part of the Great Dividing Range, which was formed by plate shift, and is (I'm pretty sure, but not 100%) not volcanic. But it does make a good multiday walk during Spring, Summer, Autumn, or a serious skitour in Winter.

For the highest volcano on the Australian mainland you'd probably be looking around Mt Warning in Northern NSW which is the plug of an ancient shield volcano. The northern section of its caldera rim forms the NSW/Qld border ranges.

okay, seriously i never really thought about the defination before, as i myself is not really equipped with any geology skill. However, when reading your post, it struck me when i come across somewhere in SP that it was mentioned, Aconcagua, has some volcanic rocks on it, but itself is not a volcano.

So bogong, is it in similar way? Previous posts even suggested that there is a side volcanic peak, and i tried googled bogong, it seems to be that there was an eruption some millions years ago...

Side volcanic peak? I think you are probably referring to the fact that Mt Bogong itself is separated from the Bogong High Plains.

I'm no geologist either, but I think you are on the right track when you consider Aconcagua in relation to nearby volcanoes. In reality all rocks are ultimately volcanic in origin but an awful lot happens during geological time and this is a very ancient continent.

I personally don't think the term "Oceania" has any real meaning, but certainly,the highest volcanoes on this particular tectonic plate are not on the Australian mainland. As mentioned above, you need to look at Papua New Guinea.

The highest volcanic peak on Australian territory is Mawson Peak in the sub Antarctic, but of course, it's not on the same tectonic plate as Australia itself.

Nope. Lots of rock is sedimentary in origin. The sediment is often biological in origin - calcium-rich shells of dead plankton, for example. (I suppose the calcium was mostly in magma during the formation of the Earth....)

edit: I think you meant "all mountains are ulitmately volcanic in origin". I think that's basically right, if extremely indirect: the himalaya, for example, are pretty far from any expanding mid-ocean ridges (definitely volcanic) that are indirectly pushing India into Asia. And for certain definitions of "mountain", I could point to peaks formed by meteor impact or a few other non-volcanic processes.

Re the "side peak": Wikipedia mentions a "bogong volcano" and maps it to a small bump in the middle of a slope, tens of miles from the summit of Mt Bogong. It's possible that's simply an incorrect set of coordinates for Mt Bogong, or it could be that "bogong volcano" means something different from "mt bogong". (Or maybe there is a "bogong volcano" that's distinct from Mt bogong, AND wikipedia has its coordinates wrong ) Wikipedia doesn't cite useful sources in this case, and I know nothing about Australian geography.

Nope. Lots of rock is sedimentary in origin. The sediment is often biological in origin - calcium-rich shells of dead plankton, for example. (I suppose the calcium was mostly in magma during the formation of the Earth....)

edit: I think you meant "all mountains are ulitmately volcanic in origin". I think that's basically right, if extremely indirect: the himalaya, for example, are pretty far from any expanding mid-ocean ridges (definitely volcanic) that are indirectly pushing India into Asia. And for certain definitions of "mountain", I could point to peaks formed by meteor impact or a few other non-volcanic processes.

Re the "side peak": Wikipedia mentions a "bogong volcano" and maps it to a small bump in the middle of a slope, tens of miles from the summit of Mt Bogong. It's possible that's simply an incorrect set of coordinates for Mt Bogong, or it could be that "bogong volcano" means something different from "mt bogong". (Or maybe there is a "bogong volcano" that's distinct from Mt bogong, AND wikipedia has its coordinates wrong ) Wikipedia doesn't cite useful sources in this case, and I know nothing about Australian geography.

well according to previous post by WillP, he did mention that bogong volcano is 25km away from mount bogong main summit. as i also obtain most of my infomation from wiki, i seriously wonder if there is a way i can contact some australian authority to comfirm about that.